经过几天的单链表学习，积累了很多单链表节点类的方法和属性，见以下代码。今天对其中的属性 values 做些修改，就能得到对应的生成器方法和属性。特别是当链表很长时，生成器比列表更节省内存空间。
class Node(): def __init__(self, value=None, Next=None): self.val = value self.next = Next if type(self.next)==Node and self.next.val==None: self.next=None def __repr__(self): return f'Node({self.val}->{self.next})' def __str__(self): return f'{self.val}->{self.next}' def __len__(self): if self.val is None: return 0 length,ptr = 0,self while ptr is not None: length += 1 ptr = ptr.next return length def __eq__(self, other): ptr1,ptr2 = self,other if len(ptr1)!=len(ptr2): return False while ptr1 is not None: if ptr1.val!=ptr2.val: return False ptr1 = ptr1.next ptr2 = ptr2.next else: return True def size(self): return self.__len__() @property def length(self): return self.size() @property def value(self): return self.val @property def values(self): ret,ptr = [],self while ptr is not None: ret.append(ptr.val) ptr = ptr.next return ret def pprint(self): items = [str(i) for i in self.values] if items==[]: print('None->None') elif len(items)==1: print(f'{items[0]}->None') else: print('->'.join(items)+'->None') def isNode(node): return isinstance(node,Node) and isinstance(node.next,(Node,type(None))) def build(*data, split=True): '''把数据转换成节点链表''' lst,ret = [],Node() for val in data: if type(val) is str: if not split: lst.append(val) continue if str=='': continue try: num = int(val) lst.extend([int(_) for _ in val]) except: lst.extend([_ for _ in val]) elif hasattr(val,'__iter__'): lst.extend([_ for _ in val]) elif type(val) is Node: if not val.isNone: lst.extend(val.values) else: lst.append(val) ret = Node() for i in lst[::-1]: ret = Node(i, ret) return ret def copy(node): ret = Node() ptr1,ptr2 = node,ret while ptr1 is not None: ptr2.next = Node(ptr1.val) ptr1,ptr2 = ptr1.next,ptr2.next return ret.next
增加链表节点数据域的遍历生成器(方法、属性)：
def items(self): ptr = self while ptr is not None: yield ptr.val ptr = ptr.next @property def generator(self): yield from self.values
yield 语法糖：yield form iterable object (python 3.3+)
等价于：
for item in iterable:
yield item
